ALPECOLE
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ALPECOLe: Glossary

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A horizon
The topsoil layer in a soil profile that commonly contains organic matter.
 
abiotic
Not related to life, purely physical-chemical processes/conditions
 
ablation
In glaciers, refers to melting, erosion and evaporation which reduces the area of the ice.
 
ablation area
The termini of glaciers where loss of ice occurs through calving, melting or evaporation
 
accumulation area
The snowfields or cirques of mountain glaciers and the snowfields of continental glaciers are called the zone of accumulation because it is here that new snow falls to nourish the glacier.
 
active layer
The layer of ground that is subject to annual thawing and freezing in areas underlain by permafrost
 
adaptation
Act of changing to fit different conditions. A change of structure, form, or habits to suit conditions, inherited within a species and increasing rates of reproduction and survival.
 
advective
The transfer of air mass properties by the velocity field of the atmosphere
 
aeolic
Wind borne, e.g. dust deposited by wind
 
agamospermy
The formation of seeds without sexual reproduction. The seeds are genetically identical to the mother plant.
 
albedo
or surface reflectivity is the ratio of the amount of electromagnetic radiation reflected by a body (surface) to the amount incident upon it, commonly expressed as a percentage. Ice may reflect up to 90 percent of incoming solar radiation (albedo = 90), while blacktop asphalt may absorb up to 95 percent (albedo = 5).
 
allophane
Clay mineral of the kaolinite group, whitish, amorphous, non-crystalline
 
alpine
of or relating to a region that occurs above the tree line and below the (permanent) snow line on temperate and tropical mountains. The vegetation is characterised by an absence of trees and varies greatly with its aspect, the greatest contrasts being between the wet side and the dry leeward side of the mountains concerned. The elevation of the lower limit of the zone increases from about 1000 m above sea level in Scotland to over 2000 m in the Swiss Alps and to 3700 m in the western Himalaya.
 
Alpine
(a) of or relating to the Alps or their inhabitants
(b) (Geology) of or relating to an episode of mountain building in the Tertiary period during which the Alps were formed
 
alpine, the
in its widest sense, any area in the belt between the high elevation treeline and the snowline. In a narrower sense, restricted to the alpine belt proper, i.e. the treeless land above the treeline with a full vegetation cover. The term applies globally just like "the tropics".
 
altiplano
High altitude plane in Latin America
 
androecium
Male part of flower
 
annoxia
Lack of oxygen
 
anthesis
The opening of a flower, sometimes used to denote the stage when the flower first donates pollen, or is receptive to pollen, whichever is earlier.
 
anthocyanid
Blue/red water soluble pigment
 
apomixis
Asexual reproduction, includes both vegetative reproduction and agamospermy.
 
apoplast
The part of a plant tissue outside the outer protoplast membrane. Commonly the sum of cell walls (cellulose) and intercellular spaces.
 
asthenosphere
A layer in the mantle that is relatively weak and viscous and lies directly beneath the solid lithosphere.
 
autogamy
Within-flower fertilisation
 

 

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29 August 2011
© ALPECOLe 2002-2007